<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        div {
            position: absolute;
            top: 0;
            left: 0;
            width: 100px;
            height: 100px;
            background-color: pink;
        }
    </style>
</head>
<body>
    <div></div>
    <script>
        var div = document.querySelector('div')
        var startX = 0;//获取手指的初始坐标
        var startY = 0;
        var x =0;//获取盒子原来的位置
        var y = 0;  
        div.addEventListener('touchstart',function(e){
            //获取元素初始坐标
            startX = e.targetTouches[0].pageX;
            startY = e.targetTouches[0].pageY;
            // 手指的初始位置
            x = this.offsetLeft;
            y = this.offsetTop;
        })
        div.addEventListener('touchmove',function(e){
           var moveX = e.targetTouches[0].pageX - startX;
           var moveY = e.targetTouches[0].pageY - startY;
           this.style.left = x + moveX + 'px';
           this.style.top = y + moveY + 'px';
           e.preventDefault();//阻止屏幕默认滚动的行为
        })

    </script>
</body>
</html>